1. Field of the Invention
The present invention relates to closures for reclosable pouches, and more particularly, to such closures that include two closure mechanisms comprised of male and female closure elements.
2. Description of the Background of the Invention
A thermoplastic pouch for the storage of items typically includes a closure mechanism comprising multiple profiles disposed on opposed inner surfaces of pouch walls. In a specific example, two sets of profiles are disposed on pouch walls wherein each set includes a male and a female closure element.
Ausnit U.S. Pat. No. 3,656,147 discloses a plastic bag having male and female resealable interlocking elements integrally attached thereto for selectively opening and closing an end of the bag. The bag further includes a pair of stiffener ribs formed integrally with the bag and disposed below the resealable elements to provide increased rigidity along an open end of the bag to prevent inadvertent separation of the elements.
Ausnit U.S. Pat. No. 4,787,880 discloses a bag having first and second zipper strip bases secured to opposing wall panels of the bag. The bases each include at least two arrow-shaped profiles extending therefrom to engage with the profiles of the opposing base, wherein the profiles of the same base are adjacent one another.
Ausnit U.S. Pat. No. 4,792,240 discloses a bag having a reclosable zipper including first and second base members each having a plurality of interlocking zipper profile parts extending therefrom. The bottom-most profile part has a head having a greater mass than the head of the other profile parts to resist opening of the zipper due to internal pressures.
Johnson U.S. Pat. No. 6,138,329 discloses a reclosable bag having an assembly that includes first and second male arrow-shaped profiles extending perpendicularly from a first base. The assembly further includes first and second female U-shaped members extending perpendicularly from a second base to engage the first and second male profiles, respectively. Each of the male arrow-shaped profiles includes two prongs extending therefrom that engage with a female profile. The prongs of the second male profile are longer than the prongs of the first male profile to increase the opening force of the second male profile when interlocked with a respective female profile.
Malin U.S. Pat. No. 6,167,597 discloses a zipper strip for a reclosable package, wherein the zipper strip includes a male and a female profile. There are at least two male interlocking members that extend from a base toward the opposite female interlocking members, wherein each male member has an asymmetrical arrow shape so that the zipper is easier to open from one side than the other. One or both of the profiles includes at least one high compression member that extends from a base thereof to touch a base of the opposite profile to allow the profiles to be sealed without crushing or distorting the interlocking members.
Linton U.S. Pat. No. 6,691,383 discloses a webless zipper for a reclosable bag including interlocking male and female profiles. The male profile includes three ribs, wherein each of two of the ribs includes double-barbed end sections at the end of a shaft. The barbs of each end section are asymmetrical with a longer barb facing a product side of the bag to increase the opening force for the product side of the bag. The female profile includes two grooves, defined by legs that interlock with the double-barbed end sections.